Add to that average stress levels from work, and keeping employees motivated to provide consistent results becomes quite the challenge. Fortunately, by fixing processes and hiring more of the right people, you can control at least part of what makes the difference between level-headed employees and overwhelmed, unproductive ones.

Sadly, when projects pile up and stress skyrockets, the last thing on your mind is hiring more people or cleaning up processes. Perhaps, though, that should be the first thing on your mind -- actually it definitely should be once the storm passes.

But you can’t increase employee motivation and quality control if you don’t first notice the telltale signs of overworked and inefficient employees. So, here are five.

1. They don’t laugh while at work.

Unhappy employees are less productive than their joyful counterparts. Specifically, one study estimates that happy employees are about 12 percent more productive than unhappy employees. That’s not surprising when you think about it. When people have less internal concerns, they produce a better quality more consistently.

Of course, running a profitable business and keeping everyone happy at the same time isn’t always easy. Still, you shouldn’t ignore the general vibe around the workplace. Do people seem like they’re enjoying their time or dreading it? Are employees so busy that they have no time to shoot the breeze with their coworkers?

Although it might seem like laughing employees kills productivity and profitability, it might actually -- as the study above suggests -- encourage a higher efficiency and quality when employees do sit down to work.

2. Miscommunications runs rampant.

Forty-four percent of workers said a serious business mistake or shortcoming has been the result of a miscommunication at some point in their professional experience. And 18 percent said that miscommunication lost a sale -- a third of those sales valued above $100,000.

For efficiency and profitability’s sake, miscommunication is one thing you don’t want running rampant around the workplace. Sadly, when employees are overworked and overstressed, miscommunications are inevitable -- and they’re often a sign that you need to hire more people, clean up processes or redistribute existing projects from certain employees.

3. They’re making rookie mistakes.

The moment your most trusted employees start making rookie mistakes is the same moment you need to examine the way you’re running your business. If you trust these employees and they’ve never let you down before, it’s probably not their fault. It’s probably the fault of unclear processes or fast growth without adequate leadership.

The reality is, most people operate best when running at about 80 percent. Even a great employee might burn out and start making silly mistakes when running at 90 or 100 percent for too long. Slow down and bring back your superstars before they burn out for good.

4. Absenteeism is on the rise.

If people aren’t showing up to work, there’s a problem. Of course, hiring slackers who don’t show up to team meetings on time, take a suspicious amount of sick days or outright miss work is often an unfortunate part of business.

To some degree, that absenteeism is impossible to completely avoid. You take chances on people and some of those people work out. Others don’t. Having said that, if new hires with high spirits and old hires with long commitments try to miss work as often as possible, then there’s a good chance you’re burning out your employees. You should reevaluate your business processes before those workers leave for good.

5. They’ve lost passion for their work.

When you hired your employees, more than likely, part of why you chose them was because they showed passion for their work. If that passion starts to fade, it might be a sign that those same employees don’t have the time or energy to pursue their greatest interests.

And that lack of employee passion is bad for business. In fact, one out of five employees want to leave their job because they simply are no longer passionate about their work. Plus, when employees lack passion for their daily work, quality of that work naturally decreases. So too does their commitment to your business.

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